Process for preparing chloromethyl 5-nitro-2-furyl ketone



United States Patent PRGCESS This invention relates to an improvedprocess for preparing chlorornetiyl -nitro-2-furyl ketone. Like manynitrofurans, this compound is a disinfactant and antiseptic. It is alsouseful as an intermediate in the preparation of other nitrofurancompounds.

Heretorore, the preparation of chloromethyl S-nitro-Z- furyl ketone hasbest been accomplished by a snythesis which involves the use ofS-nitro-Z-furoyi chloride and diazomethane. Both of these compounds haveextremely hazardous propensities requiring the exercise of great cautionin their use. While the yield of the desired end product is satisfactoryusing these reactments, their highly toxic character, especially that ifdiazomethane, makes production on a large scale nearly out of thequestion in a practical sense.

It has now been found that chloromethyl S-nitro-Z- furyl ketone can beproduced in simple and facile fashion and in high yield using reactantswhich are commonly handled with relative ease and which do not have theinsidious toxicity of those used in the past.

In accordance with this invention, chloromethyl S- nitro-Z-furyl ketoneis produced readily and cheaply by simply bringing together bromomethyl5-nitro-2-furyl ketone and hydrochloric acid.

In the practice of this invention brornornethyl S-nitro- 2-furyl ketoneis merely suspended in concentrated hydrochloric acid for a short timeand chloromethyl 5- nitro-2-furyl ketone recovered from the mixture. Thereaction is simply illustrated:

It is conveniently conducted by mixing bromomethyl 5- nitro-Z-furylketone and concentrated hydrochloric acid in a suitable reaction vessel,supplying heat briefly to said vessel until the mixture becomes clear,cooling and filtering to recover chloromethyl S-nitro-Z-furyl ketone. Atemperature of about for about 10 minutes serves to readily promote thereaction and produce a high yield of the product. The chloromethylS-nitro-Z-furyl ketone may be purified by recrystallizing from asuitable solvent such as carbon tetrachloride.

In order that this improved process may be readily available to andunderstood by those skilled in the art, a brief description of apreferred embodiment of it is supplied:

A mixture of 5 g. of brornomethyl S-nitro-Z-furyl ketone and 125 cc. ofconcentrated hydrochloric acid in a flask is heated on a steam bath atabout 80 with stirring for about 10 minutes. A clear solution isobtained. The solution is cooled in ice, ltered, and the solid obtainedwashed with cold water. The yield is 2.4 g. of chloromethylS-nitro-Z-furyl ketone, MP. -93". The filtrate and the washings are madeup to 250 cc. with cold water and allowed to stand in an ice bath for /2hour. This is filtered, and the solid obtained washed with cold Water toyield an additional 0.6 g. of chloromethyl 5- nitro2-furyl ketone, M.P.8992. The 3 g. of solid are recrystallized from cc. of carbontetrachloride to give 2.4 g., 60% overall yield of chloromethylS-nitro-Z- furyl ketone, M.P. 9697.

What is claimed is:

A process for preparing chloromethyl 5-nitro-2-furyl ketone whichcomprises bringing together bromomethyl 5-nitro-2-furyl ketone andconcentrated hydrochloric acid.

No references cited.

